Field
This disclosure relates to real-time audio processing of ambient sound.
Description of the Related Art
The world can be abusively loud, filled with noises one wants to hear mixed with sounds one does wish to hear. For example, a neighbor's baby can be crying while a sports finals game is live on television. The droning hum of an airliner engine can run while you wish to have a conversation with your nearby child. Cities are filled with sirens, subway screeches, and a constant onslaught of traffic. Environments we choose to immerse ourselves in, such as concerts and sports stadia, can be loud enough to induce permanent hearing damage in mere minutes. Prevention of these sounds is at best inconvenient and at worst impossible. There is no audio analog to sunglasses, with which users can easily and selectively shield their ears from unwanted sounds as desired.
Different approaches to deal with either too much audio or too little audio (or the two intermixed) have been devised over time. These include ear plugs, active noise cancellation (ANC), hearing aids and other, similar devices. However all of these approaches have shortcomings.
Ear plugs are more like blinders than sunglasses—they reduce (or completely remove) and muddy our audio experience too far to be enjoyable. ANC, available in many headphones and ear buds, is also a step in the right direction. But it is binary-either all the way on, or all the way off. And ANC is non-selective; it attempts to remove all sounds equally, regardless of their desirability. Both ear plugs and ANC do not discriminate between a background annoyance and a conversation you wish to have.
Hearing aid technology typically provides audio augmentation by increasing the volume of all audio received. More capable hearing aids provide some capability to increase or decrease the volume of certain frequencies. As the focus of hearing aids is typically being able to hear for comprehension of conversation with loved-ones, this is ideal. Particularly sophisticated hearing aids can be tuned to address hearing loss in specific frequency ranges. However, hearing aids typically provide no real, immediate capability to control what aspects, if any, of audio a wearer wishes to hear.
Throughout this description, elements appearing in figures are assigned three-digit reference designators, where the most significant digit is the figure number and the two least significant digits are specific to the element. An element that is not described in conjunction with a figure may be presumed to have the same characteristics and function as a previously-described element having a reference designator with the same least significant digits.